I've noticed when I'm trying to do low level melding that while a lot of the time the meld will be possible with a 100% success rate, the window will tell me the 'selected item's level is too low to maximize materia potential' usually resulting in the specified stat +0. For example if I try to put a Strength I materia into a Sunstone Ring (i29), it gives me that message despite the materia saying "item level 15" on it. How does this work?